Farmakologik xususiyatlari
Meropenem parenteral qo'llaniladigan karbapenem antibiotik bo'lib, insonning dehidropeptidaza-1 (DHP-1) ta'siriga nisbatan nisbatan barqaror, shuning uchun DHP-1 inhibitori qo'shishni talab qilmaydi.
Meropenem bakterial hujayra devorining hayotiy sinteziga aralashish orqali bakteritsid ta'sir ko'rsatadi. U bakterial hujayra devorlariga kirish osonligi, barcha serin β-laktamazlarga nisbatan yuqori barqarorlik darajasi va penitsillin bog'lovchi oqsillarga (PBP) kuchli afinitetga ega bo'lishi meropenemning keng spektrli aerob va anaerob bakteriyalarga qarshi kuchli bakteritsid ta'sirini tushuntiradi. Minimal bakteritsid konsentratsiyalar (MBK) odatda minimal inhibe qiluvchi konsentratsiyalar (MIK) bilan bir xil. 76% bakteriyalar uchun MBK/MIK nisbati 2 va undan kam edi. Meropenem sezgirlik testlarida barqaror. In vitro testlar meropenemning turli antibiotiklar bilan sinergik ta'sir ko'rsatishini ko'rsatadi. Meropenem postantibiotik ta'sirga ega.
Farmakokinetika va mikroorganizmlar uchun zona diametri va MIK ga nisbatan klinik va mikrobiologik natijalar asosida meropenemga sezgirlikning yagona kompleks mezonlari tavsiya etiladi.
Meropenemning in vitro antibakterial spektri quyida ko'rsatilganidek, ko'pchilik klinik jihatdan ahamiyatga ega gram-musbat va gram-manfiy, aerob va anaerob bakteriya shtammlarini o'z ichiga oladi.
Gram-musbat aeroblar:
Bacillus spp., Corynebacterium diphteriae, Enterococcus faecalis, Enterococcus liquifaciens, Enterococcus avium, Listeria monocytogenes, Lactobacillus spp., Nocardia asteroids, Staphylococcus aureus (penitsillinaza uchun musbat va manfiy), Staphylococcus epidermidis, Staphylococcus saprophyticus, Staphylococcus capitis, Staphylococcus cohnii, Staphylococcus xylosus, Staphylococcus warneri, Staphylococcus hominis, Staphylococcus simulans, Staphylococcus intermedius, Staphylococcus sciuri, Staphylococcus lugdunensis, Streptococcus pneumoniae (penitsillinga sezgir va qarshilik ko'rsatadigan), Streptococcus agalactiae, Streptococcus pyogenes, Streptococcus equi, Streptococcus bovis, Streptococcus mitis, Streptococcus mitior, Streptococcus milleri, Streptococcus sanguis, Streptococcus viridans, Streptococcus salivarius, Streptococcus morbillorum, Streptococcus Group G, Streptococcus Group F, Rhodococcus equi.
Gram-manfiy aeroblar:
Achromobacter xylosoxidans, Acinetobacter anitratus, Acinetobacter lwoffii, Acinetobacter baumannii, Aeromonas hydrophila, Aeromonas sorbria, Aeromonas caviae, Alcaligenes faecalis, Bordetella bronchiseptica, Brucella melitensis, Campylobacter coli, Campylobacter jejuni, Citrobacter freundii, Citrobacter diversus, Citrobacter koseri, Citrobacter amalonaticus, Enterobacter aerogenes, Enterobacter (Pantoea) aglomeran, Enterobcter cloacae, Enterobacter sakazakii, Escherichia coli, Escherichia hermannii, Gardnerella vaginalis, Haemophilus influenzae (β-laktamazaga musbat va ampisillin qarshilik ko'rsatadigan shtamlarni o'z ichiga oladi), Heamophilus parainfluenzae, Heamophilus ducreyi, Helicobacter pylori, Neisseria meningitides, Neisseria gonorrhoeae (β-laktamalarga musbat, penitsillin va spektonomitsin qarshilik ko'rsatadigan shtamlarni o'z ichiga oladi), Hafnia alvei, Klebsiella pneumoniae, Klebsiella aerogenes, Klebsiella ozaenae, Klebsiella oxytoca, Moraxella (Branhamella) catarrhalis, Morganella morganii, Proteus mirabilis, Proteus vulgaris, Proteus penneri, Providencia rettgeri, Providencia stuartii, Providencia alcalifaciens, Pasteurella multocida, Plesiomonas shigelloides, Pseudomonas aeruginosa, Pseudomonas putida, Pseudomonas alcaligenes, Burkholderia (Pseudomonas) cepacia, Pseudomonas flourescens, Pseudomonas stutzeri, Pseudomonas pseudomallei, Pseudomonas acidovorans, Salmonella spp., Salmonella enteritidis/typhi, Serratia marcescens, Serratia liquefaciens, Serratia rubidaea, Shigella sonnei, Shigella flexneri, Shigella boydii, Shigella dysenteriae, Vibrio cholerae, Vibrio parahaemolyticus, Vibrio vulnificus, Yersinia enterocolitica.
Anaerob bakteriyalar:
Actinomyces odontolyticus, Actinomyces meyeri, Bacteroides-Prevotella-Porphynomonas spp., Bacteroides fragilis, Bacteroides vulgatus, Bacteroides variabilis, Bacteroides pneumosintes, Bacteroides coagulans, Bacteroides uniformis, Bacteroides distasonis, Bacteroides ovatus, Bacteroides thetaiotaomicron, Bacteroides eggerthii, Bacteroides capsillosis, Prevotella buccalis, Prevotella corporis, Bacteroides gracilis, Prevotella melaninogenica, Prevotella intermedia, Prevotella bivia, Prevotella splanchnicus, Prevotella oralis, Prevotella disiens, Prevotella rumenicola, Bacteroides ureolyticus, Prevotella oris, Prevotella buccae, Prevotella denticola, Bacteroides levii, Porphyromonas asaccharolytica, Bifidobacterium spp., Bilophila wadsworthia, Clostridium perfringens, Clostridium bifermentalis, Clostridium ramosum, Clostridium sporogenes, Clostridium cadaveris, Clostridium sordellii, Clostridium butyricum, Clostridium clostridiiformis, Clostridium, innocuum, Clostridium subterminale, Clostridium tertium, Eubacterium lentum, Eubacterium aerofaciens, Fusobacterium mortiferum, Fusobacterium necrophorum, Fusobacterium nucleatum, Fusobacterium varium, Mobiluncus curtisii, Mobiluncus mulieris, Peptostreptococcus anaerobius, Peptostreptococcus micros, Peptostreptococcus saccharolyticus, Peptococcus saccharolyticus, Peptostreptococcus asaccharolyticus, Peptostreptococcus magnus, Peptostreptococcus prevotii, Propionibacterium acnes, Propionibacterium aidum, Propionibacterium granulosum.
Stenotrophomonas maltophilia, Enterococcus faecium va metitsillin qarshilik ko'rsatadigan stafilokoklar meropenemga qarshi qarshilik ko'rsatadi.
Farmakokinetika
Intravena kiritilgandan so'ng, dozaga (0,5 yoki 1 g) va kiritish usuliga (bolus yoki tomchilab) qarab, preparatning qon plazmasidagi maksimal konsentratsiya qiymati (Cmax) 23 mkg/ml, 45 mkg/ml, 49 mkg/ml va 112 mkg/ml ni tashkil etadi. Plazma oqsillari bilan 2% bog'lanadi. Turli to'qimalar va inson organizmi suyuqliklariga (spinal suyuqlikni o'z ichiga olgan holda) oson kiradi, bakteritsid konsentratsiyalar kiritilgandan so'ng 0,5-1,5 soat ichida erishiladi. Jigar tomonidan bitta metabolit (farmakologik jihatdan faol bo'lmagan) hosil bo'lishi bilan oz miqdorda biotransformatsiyaga uchraydi. Preparatning yarim hayot davri (T ½) 1 soatni tashkil etadi. Asosan buyraklar orqali chiqariladi (70% dan ortig'i o'zgarmagan holda chiqariladi). Buyrak yetishmovchiligi holatida meropenemning plazma klirensi kreatinin klirensining pasayishi darajasiga to'g'ridan-to'g'ri bog'liq.
Meropenemning bolalardagi farmakokinetikasi kattalardagi kabi. 2 yoshgacha bo'lgan bolalarda preparatning yarim hayot davri taxminan 1,5-2,3 soatni tashkil etadi, bunda 10-40 mg/kg dozalar oralig'ida "konsentratsiya-doza" chiziqli bog'liqligi kuzatiladi. Qariyalar orasida meropenem klirensi pasayadi, bu yoshga bog'liq kreatinin klirensining pasayishi bilan bog'liq.
Meropenemning buyrak yetishmovchiligi bo'lgan bemorlardagi klirensi kreatinin klirensiga bog'liq. Shuning uchun kreatinin klirensi oshgan bemorlarga preparatning dozasini tuzatish zarur. Meropenemning jigar kasalliklari bo'lgan bemorlardagi farmakokinetikasi o'zgarmaydi.